1. Field of the Invention
The present invention relates to a coating agent for forming a fine pattern which is used for forming a fine resist pattern, and a method for forming a fine pattern which forms a fine resist pattern using the coating agent for forming a fine pattern.
2. Related Art
In the production of electronic components, such as semiconductor devices and liquid crystal devices, photolithographic techniques have been used when a process such as etching is performed on a substrate. In the photolithographic techniques, a coat film (resist layer) is formed on a substrate using a so-called photoresist material responsive to actinic radiation, then the resist layer is selectively irradiated with the actinic radiation in order to perform light exposure, and thereafter a developing treatment is performed to selectively dissolve and remove the resist layer so as to form an image pattern (resist pattern) on the substrate. Then, a wiring pattern is formed on the substrate by carrying out an etching process with this resist pattern as a protective layer (mask pattern).
In unison with a recent growing tendency to highly integrate and miniaturize semiconductor devices, fine-fabrication in the formation of these resist patterns has also advanced and thus ultra-fine-processing is required. In addition to attempt to achieve such ultra-fine-fabrication of the resist pattern, research and development of techniques have been performed in order for the pattern fine-fabrication to exceed the resolution limit of the resist materials also in view of pattern formation methods.
As a method for forming an ultra-fine resist pattern, for example, a method is known for obtaining an ultra-fine resist pattern by forming a coat film composed of a coating agent for forming a fine pattern including a water-soluble polymer on the surface of a resist pattern formed on a substrate, followed by thermal-shrinking the formed coat film to narrow down the intervals of the resist pattern.
In detail, for example, a coating agent for forming a fine pattern has been proposed, which includes (A) a water-soluble polymer, and (B) at least one selected from quaternary ammonium hydroxide, alicyclic ammonium hydroxide, and morpholinium hydroxide (Patent Document 1).
[Patent Document 1] Japanese Unexamined Patent Application, Publication No. 2008-180813